mm: Never allow allocations more than our physical memory

This should provide faster allocations than OVERCOMMIT_GUESS, without
the significant OOM risk of OVERCOMMIT_ALWAYS.

Signed-off-by: Tyler Nijmeh <tylernij@gmail.com>

Author: tytydraco

mm/util.c

@@ -486,8 +486,8 @@ int __page_mapcount(struct page *page)
 }
 EXPORT_SYMBOL_GPL(__page_mapcount);
 
-int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_GUESS;
-int sysctl_overcommit_ratio __read_mostly = 50;
+int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_NEVER;
+int sysctl_overcommit_ratio __read_mostly = 100;
 unsigned long sysctl_overcommit_kbytes __read_mostly;
 int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;
 unsigned long sysctl_user_reserve_kbytes __read_mostly = 1UL << 17; /* 128MB */